PR https://github.com/ziglang/zig/pull/20679 ("std.c reorganization")
switched feature-detection code to use "T != void" checks in place of
"@hasDecl". However, the std.posix.system struct is empty, so
compile-time feature detection against symbols in there (specifically
`std.posix.system.ucontext_t` in this case), fail at compile time on
freestanding targets.
This PR adds a void ucontext_t into the std.posix.system default.
This PR also adds pseudo-"freestanding" variation of the StackIterator
"unwind" test. It is sort of hacky (its freestanding, but assumes it can
invoke a Linux exit syscall), but it does detect this problem.
Fixes#20710
The set of signals that cannot have their action changed is documented in POSIX,
and any additional, non-standard signals are documented by the specific OS. I
see no valid reason why EINVAL should be considered an unpredictable error here.
* common symbols are now public from std.c even if they live in
std.posix
* LOCK is now one of the common symbols since it is the same on 100% of
operating systems.
* flock is now void value on wasi and windows
* std.fs.Dir now uses flock being void as feature detection, avoiding
trying to call it on wasi and windows
It is now composed of these main sections:
* Declarations that are shared among all operating systems.
* Declarations that have the same name, but different type signatures
depending on the operating system. Often multiple operating systems
share the same type signatures however.
* Declarations that are specific to a single operating system.
- These are imported one per line so you can see where they come from,
protected by a comptime block to prevent accessing the wrong one.
Closes#19352 by changing the convention to making types `void` and
functions `{}`, so that it becomes possible to update `@hasDecl` sites
to use `@TypeOf(f) != void` or `T != void`. Happily, this ended up
removing some duplicate logic and update some bitrotted feature
detection checks.
A handful of types have been modified to gain namespacing and type
safety. This is a breaking change.
Oh, and the last usage of `usingnamespace` site is eliminated.
Instead of calling the dynamically loaded kernel32.GetLastError, we can extract it from the TEB.
As shown by [Wine](34b1606019/include/winternl.h (L439)), the last error lives at offset 0x34 of the TEB in 32-bit Windows and at offset 0x68 in 64-bit Windows.
Using std.os.linux directly in e.g. std.posix.timerfd_create() causes
the function to compile but silently fail at runtime when targeting any
OS other than Linux.
To catch errors like this at compile time, std.os.linux must only be
directly accessed within std.posix where there has been a comptime check
that the target os is in fact Linux.
Before this commit, the DIRECTORY_NOT_EMPTY/FILE_IS_A_DIRECTORY/NOT_A_DIRECTORY statuses were assumed only to be possible when using `FILE_RENAME_INFORMATION_EX` and `FILE_RENAME_POSIX_SEMANTICS`, but that has empirically been shown to be false; a networked samba share can return the DIRECTORY_NOT_EMPTY status from `FILE_RENAME_INFORMATION` (which doesn't support `FILE_RENAME_POSIX_SEMANTICS`).
`FILE_IS_A_DIRECTORY` and `NOT_A_DIRECTORY` were not proven to be possible, but they were also moved to the outer switch just in case.
Fixes#19785
Deprecated aliases that are now compile errors:
- `std.fs.MAX_PATH_BYTES` (renamed to `std.fs.max_path_bytes`)
- `std.mem.tokenize` (split into `tokenizeAny`, `tokenizeSequence`, `tokenizeScalar`)
- `std.mem.split` (split into `splitSequence`, `splitAny`, `splitScalar`)
- `std.mem.splitBackwards` (split into `splitBackwardsSequence`, `splitBackwardsAny`, `splitBackwardsScalar`)
- `std.unicode`
+ `utf16leToUtf8Alloc`, `utf16leToUtf8AllocZ`, `utf16leToUtf8`, `fmtUtf16le` (all renamed to have capitalized `Le`)
+ `utf8ToUtf16LeWithNull` (renamed to `utf8ToUtf16LeAllocZ`)
- `std.zig.CrossTarget` (moved to `std.Target.Query`)
Deprecated `lib/std/std.zig` decls were deleted instead of made a `@compileError` because the `refAllDecls` in the test block would trigger the `@compileError`. The deleted top-level `std` namespaces are:
- `std.rand` (renamed to `std.Random`)
- `std.TailQueue` (renamed to `std.DoublyLinkedList`)
- `std.ChildProcess` (renamed/moved to `std.process.Child`)
This is not exhaustive. Deprecated aliases that I didn't touch:
+ `std.io.*`
+ `std.Build.*`
+ `std.builtin.Mode`
+ `std.zig.c_translation.CIntLiteralRadix`
+ anything in `src/`
Also removes the LOCK namespace from std.c.wasi because wasi libc does
not have flock.
closes#19336
related to #19352
Co-authored-by: Ryan Liptak <squeek502@hotmail.com>
This was a mistake from day one. This is the wrong abstraction layer to
do this in.
My alternate plan for this is to make all I/O operations require an IO
interface parameter, similar to how allocations require an Allocator
interface parameter today.
